Noxious odors or gaseous fumes present in commodes and in areas about commodes have always been a normal but unpleasant result attendant commode use. These odors are especially prevalent in areas containing many commodes, when a commode is contained in a small room, such as in mobile homes, trains, buses or airplanes, and also with portble commodes not housed in a separate room, such as bedpans. In the past, venting systems attempting to remove noxious odors resulting from commode use have employed suction manifolds which conform to the configuration of and are usually attached directly to the commode seat. However, these venting systems have merely attempted to remove air and fumes from within the commode through the suctioning of the air containing noxious fumes from within the bowl of the commode.
One such system is disclosed in U.S. Pat. No. 1,972,076 to Cross which utilizes an outlet suction chamber attached between the seat and the bowl of the commode or toilet. The problem with Cross is that a substantial amount of the noxious odors may escape from the bowl of the commode into the immediate vicinity. The suction outlets in Cross are placed at the top of the bowl and thus do not operate to remove odors until the odors rise nearly to the top of the bowl. Once a user rises from a commode it becomes an open chamber.
Therefore, under the Cross disclosure, any noxious fumes which ahve not reached to top region of the bowl, before it becomes an open chamber, are allowed to escape and pollute the breathing medium of the user.
Another such system is shown in U.S. Pat. No. 2,151,138 to Morris wherein there is disclosed a suction duct arrangement similar to Cross located toward the outer margin of the bowl. As in Cross, odorous gases may escape the bowl once the user rises due to less of vacuum and an incomplete evacuation of the fumes. Other U.S. patents, such as those of U.S. Pat. Nos. 2,988,756, to Hartley and 4,094,023 to Smith, also rely solely on a similar arrangement of suction ducts in communication with the interior of the bowl of the commode. All of the above-mentioned systems, and systems employing similar structure, rely solely upon the suction present at various suction ports for the removal of the noxious fumes. As mentioned above, however, a problem exists in that the commode, being essentially an open chamber when not occupied, may allow much of the noxious gases to escape the bowl when not actually occupied. Further, it is difficult to obtain a proper flow of air and gaseous fumes out of the bowl, in such systems, necessary for complete removal of the entire mass of noxious gases present in the commode during use because the admission of air to the bowl to achieve such flow is usually mostly blocked by the user, particularly when the occupant is obese.